Back to Search
Start Over
Fluorescence bio-barcode DNA assay based on gold and magnetic nanoparticles for detection of Exotoxin A gene sequence
- Source :
- Biosensorsbioelectronics. 92
- Publication Year :
- 2016
-
Abstract
- Bio-barcode DNA based on gold nanoparticle (bDNA-GNPs) as a new generation of biosensor based detection tools, holds promise for biological science studies. They are of enormous importance in the emergence of rapid and sensitive procedures for detecting toxins of microorganisms. Exotoxin A (ETA) is the most toxic virulence factor of Pseudomonas aeruginosa. ETA has ADP-ribosylation activity and decisively affects the protein synthesis of the host cells. In the present study, we developed a fluorescence bio-barcode technology to trace P. aeruginosa ETA. The GNPs were coated with the first target-specific DNA probe 1 (1pDNA) and bio-barcode DNA, which acted as a signal reporter. The magnetic nanoparticles (MNPs) were coated with the second target-specific DNA probe 2 (2pDNA) that was able to recognize the other end of the target DNA. After binding the nanoparticles with the target DNA, the following sandwich structure was formed: MNP 2pDNA/tDNA/1pDNA-GNP-bDNA. After isolating the sandwiches by a magnetic field, the DNAs of the probes which have been hybridized to their complementary DNA, GNPs and MNPs, via the hydrogen, electrostatic and covalently bonds, were released from the sandwiches after dissolving in dithiothreitol solution (DTT 0.8 M). This bio-barcode DNA with known DNA sequence was then detected by fluorescence spectrophotometry. The findings showed that the new method has the advantages of fast, high sensitivity (the detection limit was 1.2 ng/ml), good selectivity, and wide linear range of 5–200 ng/ml. The regression analysis also showed that there was a good linear relationship (∆F=0.57 [target DNA]+21.31, R2=0.9984) between the fluorescent intensity and the target DNA concentration in the samples.
- Subjects :
- Transfer DNA
DNA, Bacterial
Virulence Factors
Bacterial Toxins
Biomedical Engineering
Biophysics
Exotoxins
Metal Nanoparticles
Nanotechnology
02 engineering and technology
Biosensing Techniques
010402 general chemistry
01 natural sciences
DNA sequencing
chemistry.chemical_compound
Limit of Detection
Complementary DNA
Electrochemistry
Pseudomonas exotoxin
Humans
Pseudomonas Infections
Magnetite Nanoparticles
ADP Ribose Transferases
Hybridization probe
General Medicine
021001 nanoscience & nanotechnology
0104 chemical sciences
Spectrometry, Fluorescence
chemistry
Colloidal gold
Pseudomonas aeruginosa
Gold
0210 nano-technology
DNA Probes
Biosensor
DNA
Biotechnology
Subjects
Details
- ISSN :
- 18734235
- Volume :
- 92
- Database :
- OpenAIRE
- Journal :
- Biosensorsbioelectronics
- Accession number :
- edsair.doi.dedup.....82b7ca6abbf90bd66ca09265a61fcbb5